On 10/22/2015 8:29 AM, Nikolay Shuyskiy wrote:
> I imagined that I could, say, add two new nodes to SolrCloud, and split
> shard so that two new shards ("halves" of the one being split) will be
> created on those new nodes.
>
> Right now the only way to split shard in my situation I see is to create
> two directories (shard_1_0 and shard_1_1) and mount new volumes onto
> them *before* calling SPLITSHARD. Then I would be able to split shards,
> and after adding two new nodes, these new shards will be replicated, and
> I'll be able to clean up all the data on the first node.
The reason that they must be on the same node is because index splitting
is a *Lucene* operation, and Lucene has no knowledge of Solr nodes, only
the one index on the one machine.
Depending on the overall cloud distribution, one option *might* be to
add a replica of the shard you want to split to one or more new nodes
with plenty of disk space, and after it is replicated, delete it from
any nodes where the disk is nearly full. Then do the split operation,
and once it's done, use ADDREPLICA/DELETEREPLICA to arrange everything
the way you want it.
Thanks,
Shawn
